Hot Weather Forces Partial Shutdown of TVA Nuclear Plant
BIRMINGHAM, Ala. - One reactor at a north Alabama nuclear plant was idle Friday and two others operated at reduced power because of the record-breaking heat wave, an outage that an industry watchdog said could be a sign of trouble for nuclear energy in a warming climate.
The Tennessee Valley Authority said it shut down the Unit 2 reactor at Browns Ferry Nuclear Plant and scaled back operations 25 percent at the plant’s other two reactors because of overheated water in the Tennessee River, which is used to cool the plant.
“This all comes down to the drought and the hot weather,” said plant spokesman Jason Huffine.
Industry watchdog David Lochbaum said the shutdown highlights a problem for nuclear power even as it is touted as environmentally friendly by President Bush, who visited Browns Ferry in June.
“This is an unforeseen impact of global warming. These plants don’t do very well in extremely hot weather,” said Lochbaum, a former Browns Ferry engineer now with the Union of Concerned Scientists in Washington.
Ken Clark, a spokesman with the Nuclear Regulatory Commission in Atlanta, said such shutdowns were rare but had occurred elsewhere.
Air temperatures soared to 105 degrees in north Alabama Thursday afternoon. Around that time, the temperature of the water downstream from the plant reached 90 degrees, the limit set by environmental regulators.
TVA spokesman John Moulton said operations were scaled back because of the high temperature of the water. Unit 2 was shut down, and Units 1 and 3 were reduced to 75 percent of their capacity.
Cutting back on power production reduces the temperature of the water discharged by the plant into the river, and that helps keep the river cooler, said Moulton.
“We did the environmentally responsible thing and limited operations,” said Huffine. Units 1 and 3 were being taken back to near full power on Friday to meet power demand, he said, but Unit 2 remained idle.
Lochbaum said Browns Ferry can’t efficiently turn water into steam or return it to its liquid form if its temperature is above 90 degrees.
“There’s not a reactor safety issue, there’s an economic issue,” he said. “These plants were designed for cooler temperatures. If something drives those up — whether it’s global warming or whatever — you have to account for that.”
The U.N. Intergovernmental Panel on Climate Change concluded earlier this year that global temperatures could rise as much as 11 degrees Fahrenheit by 2100 and that climate change already is affecting animal and plant life.
A TVA study from 2005 predicted that operations at Browns Ferry would have to be scaled back once every three to five years and could be completely shut down because of overheated discharge water.
Alabama has had 11 straight days with triple-digit temperatures, breaking records that dated back to 1881 in some areas.
Browns Ferry is located about 95 miles north of Birmingham. Bush visited the plant in June after operators restarted Unit 1, marking the first time in 22 years that all three of its reactors were on line at the time time. They had been shut down amid safety problems.
© 2007 The Associated Press.
I presumed that the water was used in cooling towers and not pot back into the river, however the article says that they DO discharge back into the river! The cooling towers would add to the oppressive humidity already present in that region. The interesting part is that if they used wind, solar and pumped hydro, they probably would not need that nuclear plant at all.
What do you suppose that discharged water carries? Please don’t anyone tell us it does not contain ANY radio-active particles.
Nuclear power has only been viable at all because it is politically promoted, economically subsidized, and environmentally ignored. If not already recognized, it will be eventually: nuclear power is a disaster on all counts.
Climate Deniers = Climate Dodos
“The Dodo (Raphus cucullatus) was a flightless bird that lived on the islands of Mauritius. Related to pigeons and doves, it stood about a meter tall (three feet), lived on fruit and nested on the ground.
“The dodo has been extinct since the mid-to-late 17th century. It is commonly used as the archetype of an extinct species because its extinction occurred during recorded human history, and was directly attributable to human activity. The phrase “as dead as a dodo” means undoubtedly and unquestionably dead.” — Wikepedia
I did forsee this problem.
The water always begins and ends in the river. The cooling towers are there to do exactly what the name says. Water from the reactor that’s too warm to put back into the river is cooled by the cooling towers. A cooling tower basically just drops water down through the air and cools the water this way.
The water in the river is warmer when it enters the plant. Its still heated in the plant. Its still cooled by the cooling towers and ponds. But cooling is less effective because its happening in warmer air. Meanwhile the water in the river that never enters the plant is warmer and closer to the 90 deg F limit said by regulators. So the power plant can’t dump its warmer than normal water from the plant without raising the river temp above the set limit.
The really funny thing is this. The way the economics of a nuclear power plant work, the utility depends on it being available during a heat wave. Once you set a nuclear plant running, it runs 24\7 for about 18 months until it shuts down and refuels and does some maintenance. So this is the power source the utility counts on being there. It fires up other plants like gas power plants when the load gets more than the nuclear produces. But that’s expensive to the power company and they’d rather just run the nuclear plant they have to run 24\7 anyways.
Instead, TVA is shutting down their nuclear plants just at the time every air conditioner in the region turns on at the peak of a hot day. TVA must have been running every other power plant full blast to try to make up, and may have been buying energy on expensive spot markets.
If these plants shut down exactly at the same time that customers demand the most power, that makes the economics of a nuclear plant even worse than anyone thought.
PS … In the main type of reactor in the US, there are two loops of water. There’s one that runs through the core. That water gets somewhat contaminated and is treated as waste (or should be). The other loop never touches the reactor. Instead, there’s a device called heat exchanger that moves the heat from one loop to another loop. Typically its something like one pipe is inside the other. Picture the pipe with hot (and contaminated water) inside another pipe with the cooler (and cleaner) water. This pulls the heat out of the reactor. This is the water that then goes to the cooling towers to be cooled down and then out tot he river.
Of course, the above assumes the pipes are in perfect condition and there are no leaks from the contaminated water pipes to the cleaner water pipes. So, while the theory is that the water going back to the river should be clean water that never went near the core, I’d still say someone should grab a sample and look at it every once in awhile.
The last irony …. solar power would of course be kicking ass during a heat wave.
On my roadtrips out West, I’ve passed through Arco, Idaho, and the INEEL area a few times. Arco has “bragging rights” of being the first atomic powered city, but it’s mostly a ghost town today. The rivers are generally all dammed in that region too. Idaho in many ways is a poster-child for what not to do with energy.
Anyway, the reason I bring it up is that they dumped nuclear reactor water into the Snake River underground acquifer and — you guessed it — contaminated the hell out of it for centuries to come: http://www.snakeriveralliance.org/
I live about 25 miles from Brown’s Ferry as the crow flies.
I was a member of a group that opposed the TVA’s nuclear power program back in’76.
Given that TVA was probably the highest paying job in the area we were as popular as a turd in a wedding cake.
In fact many of the meetings were held in one of the leaders’ homes. That will tell you how small the group was:).
This leaders’ home was burnt to the ground, by the way.
I’m sure that it was just a coincidence though:).
Back then we were protesting the planned construction of SEVERAL more reactors.
Eventually the economics of nuclear power shut down construction.
Construction on those plants is now being cranked back up.
The area around here has NO NEED for the plants.
TVA was/is being used as a way to produce power and ship it elsewhere.
That same plant very nearly had a melt-down in 1975.
However NO airborne radiation whatsoever escaped.
How do I know this?
Because ALL the air monitoring stations DOWNWIND from the plant just coincidentally happened to not be working on that day.
So yeah……I have changed my tune and am now a HUGE SUPPORTER of nuclear power today……
http://pointfocus.com/ is my site I put up //99% of the people In the U.S.
have no knowledge of high temperature point focus solar thermal concentrators
At a time when the feds want nukes which are 17% of world power to be 40% of world power by 2050
from creationism to to the physics of the controlled demolition of the WTC the public seems alarmingly held scientifically illiterate//my hope is that the doubling of the power of the CPU every 18 months is putting the analytical power of seeing into government fraud //coal and nukes should be stopped as soon as poossible//we need a massively mirrored future (as in solar thermal concentrators)
People and species right to a sustainable environment must trump corporate right to exist.Corporations acquisition of the powers and rights given to people by the U.S. constitution have created corporate super people only dedicated to profit and blind to reality and truth upon which our survival depends.
We are creating a civilization and hopefully it can be transparent, just,and recognize that the toxicity of our civilization must be changed for our ecosystem to survive.
Maybe it’s because I’m not an engineer, but it seems to me that if you can’t safely run a powerplant at 105 F (or around 40C, if I take off my shoes to do the math), there isn’t much point in having it.
I confess to being one of those Americans who was ignorant until a few minutes ago about this problem. Naively, I rather thought that things would be better designed than that.